The point has already been made that different people/roles require different things. No matter what, I would always find the YT link, download the file and work on it within some sort of transcription software (I have settled on Transcribe! after a number of years). No matter whether I can easily hear it or not, I have been making charts as a reminder of the chords AND the form of the tune. Coming into the gig I can easily listen and remember tunes, but then after not playing a tune for a year or two, coming back to it is often at least a temporary blank for me (I'm old enough to have forgotten more tunes than I can currently remember!). So my chart is a quick reminder for me, even if I don't need to keep looking at it on the gig. Just a good jump-start to get my synapses firing again.
I think a good leader would prep both a playlist and YT links, but whatever the case, I take care of what I need in my preferred fashion.
Jerry